The present invention relates to a GPS (Global Positioning System) wave antenna apparatus mounted on part of an automobile and the like.
In a conventionally-known GPS wave antenna apparatus, an antenna element of thin-plate conductor is formed on the surface of a dielectric block made of ceramics and the like as a patch antenna, and this patch antenna is placed on the surface of a printed circuit board. In most cases, an LNA (Low Noise Amplifier) including a transistor, a resistor and a capacitor is mounted on the back of the printed circuit board. For the above antenna using a dielectric, a ground plate is generally formed on the back of the antenna.
The GPS wave antenna apparatus having the above constitution causes the following problem. Since the printed circuit board is bonded to the patch antenna having a considerably great thickness, the total thickness of the antenna apparatus is increased. Since, furthermore, the ground plate is mounted on the back of the patch antenna, the thickness of the antenna apparatus is increased greater or greater. Since the antenna apparatus has a three-layered structure of the patch antenna, printed circuit board and ground plate, its structure is considerably complicated, its manufacture is difficult, and its manufacturing cost is high.